Semiconductors Questions and Answers

d both the depletion region and barrier height are increased A light emitting diode LED has a volgate drop of 2 volt across it and passes a current of 10 mA when it operates with a 6 volt battery through a limiting resistor R The value of R is a 40 k b 4 k c 200 k d 400 k 18 For a given circuit of ideal p n junction diode which of the following is correct

P is used to determine the polarity of the selected status bit MUX 2 G Input logic When P 0 T G because GO G When P 1 T G because G I G Where G is the value of the selected bit in MU 2

5 An intrinsic Silicon has 1 billion free electrons at room temperature If the temperatur doubles how many holes will be there A zero B more than 1 billion C less than 1 billion D 1 billion

Run the simulation with a comparison between the old fashioned light bulb and the high efficiency light bulb M In 5 or more sentences explain the difference in your observation of the two bulbs You can look up some information on the internet about the difference between the two types of bulbs to support your answer Do not copy information from the internet You can type your answer on the next slide

Passage III The Carlingford Igneous Centre CIC was a site of volcanic activity in Ireland during the Ordovician Period that spanned 485 to 483 million years ago This type of volcanism is an example of bimodal volcanism in which both basalt and rhyolite magma are found in the core of the volcano This results in particularly violent eruptions Scientists studied the geological makeup of the CIC and discovered that this bimodal volcanism may be caused by the geological features of the rocks underneath the volcano Figure I illustrates a cross section of the rare earth element content of various CIC site Figure 2 shows the relationship between the niobium Nb and zirconium Zr content of crustal rocks found at the CIC site Volcanic activity can influence global climate and trigger cold events The injection of sulfur dioxide gas SO which is ultimately converted to sulfuric acid aerosol particles H SO scatters shortwave solar radiation and absorbs near infrared solar radiation and outgoing longwave terrestrial radiation This results in cooling of the troposphere and heating of the stratosphere Figure 3 shows the results of a study that examined the effect of erupting volcanoes on the number of cold events in Ireland 110 100 90 80 70 60 5 4 3 Set Three Key sites Figure 1 basalt rhyolite andesite trachyandesite 50 1 2 3 4 5 6 7 8 9 10 11 12 13 14 40 35 30 25 20 215 widd qN number of cold events 10 5 0 25 10 0 0 Oct Sep MS 100 X Nov Dec LC limestone 200 Jan Feb 300 Zr ppm Figure 2 fractionation Mar 12 contamination month Figure 3 Apr 400 total volcanic Key May non volcanic Jun 102 Jul 500 Aug 11 According to the information in Figure 1 as the cross sectional altitude of trachyandesite increases from Site 5 to Site 6 the amount of andesite A increases B remains the same C increases then decreases D decreases 12 According to Figure 3 as the number of volcanic events increases from 4 to 12 the overall number of cold events F increases only G decreases only H increases then decreases J decreases then increases dons 13 According to the information in Figure 3 does the total number of cold events depend on volcanic activity A Yes because as volcanic activity based cold events increase the total number of cold events increase B Yes because as volcanic activity based cold events increase the total number of cold events remain constant C No because as volcanic activity based cold events increase the total number of cold events increase No because as volcanic activity based cold events increase the total number of cold events remain constant D 14 According to Figure 1 as the cross sectional altitude of basalt decreases from Site 1 to Site 3 does the cross sectional altitude of rhyolite and andesite increase or decrease 04 F Rhyolite increases andesite increases G Rhyolite increases andesite decreases H Rhyolite decreases andesite increases J Rhyolite decreases andesite decreases 15 According to Figure 2 the relationship between Nb content and Zr content is best represented by A Nb 3 0 x Zr B Nb Zr 3 0 Zr C Nb 12 2 D Nb 12 2 x Zr END OF SET THE STOP DO NOT GO ON TO THE NEXT F UNTIL TOLD TO DO

Q2 A Derive the governing equation for a three element viscoelastic model as shown in figure 6 mark B Explain briefly the Heterogeneity Anisotropy o Asymmetry and orthotropic material properties of the bone 4 mark 71 E ww www E

Write a hypothesis about the pH level of common household solutions based on what you know about their physical and chemical properties Use the format of if then because and be sure to answer the lesson question How is pH used to determine if a solution is acidic or basic

P www li 5 km2 D2 KH 10 kn D www a 1 k 15 V 10 k 5 kn V www 2 2 k D V 6 Vo 15 V 3 V o 1 5 k D 1 V b 15 V www li 1 k

Ind the values of I and V for the circuits of Figure P10 36 assuming that the diodes are ideal 10 V 2 7 k EDHI a V 0 10 V 10 mA 2 7 k KHII b V V d 1 k Figure P10 36 10 V 2 7 kQ2 V 2 7 kQ 1 c KH 1 kn V

The required conductivity of an n-type silicon sample at T = 300 K is to be σ = 10 (2-cm)-¹. What donor impurity concentration is required? What is the electron mobility corresponding to this impurity concentration? (b) A p-type silicon material is required to have a resistivity of p = 0.20 (-cm What acceptor impurity concentra- tion is required and what is the corresponding hole mobility?

A copper wire has a resistance of 0.495 2 at 20.0°C, and an iron wire has a resistance of 0.519 2 at the same temperature. At what temperature are their resistances equal? The temperature coefficient of resistivity for copper is 3.90 x 10-3(°C)-1 and for iron it is 5.00 x 10-³(°C)-¹.

Burning of a matchstick is an example of a __ physical change chemical change both physical and chemical changes endothermic change

Write and present a persuasive speech of at least 600 words (your speech should be about three to four minutes) based on one of the following prompts: a. Is Thornton Wilder's manipulation of time and use of flashbacks in Our Town effective or ineffective?

Which best describes an example of an n-type semiconductor? It uses phosphorus so that electrical conduction is due to the movement of electrons. It uses phosphorus so that electrical conduction is due to the movement of a positive charge. It uses gallium so that electrical conduction is due to the movement of electrons. It uses gallium so that electrical conduction is due to the movement of a positive charge.

Who did NOT benefit from the work of political machines? Party bosses Recent immigrants City governments Construction companies

One mole of atoms consists of 6.02 x 10^23 individual atoms. If 3.00 moles of atoms were spread uniformly over the Earth's surface, how many atoms would there be per square meter? The radius of Earth is 6.38 x 10^3 km. Express your answer using three significant figures.

The saturation current for a junction diode is 18 microamps. Calculate the resistance of the diode at forward potential differences of 0.20 V when T = 17°C. Express your answer with the appropriate units. Calculate the resistance of the diode at reverse potential differences of 0.20 V when T = 17°C. Express your answer with the appropriate units.

One way to approach Internet search engines and directories effectively and efficiently is to use Boolean operators. Which of the following is not a Boolean operator? and or not All of the above are Boolean operators.

i. In no more than 50 words, explain why doping is essential for imparting specific properties to intrinsic semiconducting material such as Si. ii.Give two reasons why ion implantation doping is better than diffusion doping.

A pure Si sample at 20°C has density 5x10^28. Number of thermally generated electron-hole pairs are 1.5 x 10^16 at this temperature. Now, the pure Si sample is doped with Al atoms at the rate of 1 atom per 10^7 Si atoms, which results increment in conductivity increases at the rate of 5% perºC. Compute the conductivities of pure Si, extrinsic Si and at 34°C.

Design a step-up transformer. Draw the schematic of your step-up transformer to step-up the voltage from 50 V to 200 V and discuss the following parameters; a. Np: primary winding turns b. Ns.: secondary winding turns c. N: Turns ratio d. Relate primary and secondary turns ratio to primary and secondary voltages of your designed transformer and verify the results

andA hole in a copper plate has a radius of 5 cm at 20 degree C. When the plate is heated to 200 degree C. find a) If the hole increased or decreased? b) what is the new radius of the hole? c) the change in the area of the hole.